1 kilo prawns (25 pices) shelled but with tails intact
2 tbsp. calamansi juice
salt, pepper, vetsin to taste
1 cup cooked ham, chopped
1 piece egg
1/4 cup flour
white lumpia wrapper
1/4 cup sesame seeds
oil for frying

BATTER:
2 eggs slightly beaten
1/3 cup cornstarch
salt, pepper, vetsin to taste

SWEET AND SOUR SAUCE:
1 cup vinegar
1 cup sugar
1 tsp. salt
1 tbsp. soy sauce
1/4 cup tomato sauce
2 tbsp. cornstarch dissolved in little water
dash of pepper

Shell shrimps and remove head but with tails intact. Slice each prawn lenghtwise, butterfly style. Marinate in juice and seasonings. Set aside. Mix slightly beaten eggs, chopped ham, flour and seasonings. Spread ham mixture in center of each prawn. Fold together and wrap with lumpia wrapper. Dip in batter and then roll in sesame seeds. Fry in hot oil until golden brown. Serve with Sweet and Sour Sauce.

Batter:
Mix all ingredients until smooth.

Sweet and Sour Sauce:
Mix all ingredients in a saucepan and cook in slow flame until thick.